Light-sensitive materials are distributed to users via various routes after production thereof. In the case of color printing paper, the light-sensitive material is often subject to various temperatures before reaching the photo-finisher and stored under non-refrigerating conditions due to the limited space even in the photo-finishing laboratory, even thougt an instruction for refrigerating storage is given. For this reason, the sensitivity and fogging at the time of use by the user often differ from those at delivery from the factory, which can hamper the obtainment of satisfactory performance. This is critical at increased levels of fogging, which can spoil the commercial value. Thus, there has been demand for a light-sensitive material with excellent storage stability at various temperatures in the photographic industry. In recent years, rapid processing of color photographic paper has been achieved by the use of silver halide grains with high silver chloride contents, as disclosed in WO87-04534; however, such silver halide grains are also known to be poor in the abovementioned storage stability. Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) No. 6940/1990 discloses a technique for making the surface pH on the emulsion layer side of a light-sensitive material fall between 4.0 and 5.3 to solve the above problem. Specifically, each coating solution is adjusted with respect to pH and a carbamoylpyridium hardener and a bisformazinium hardener are used. However, analyses by the present inventor revealed that this method has no effect on sensitivity fluctuation, though it has a slight effect on fogging fluctuation. Also, the use of a large amount of a 1,3,5-triazine hardener has been found to improve fogging fluctuation in storage by making the surface pH of the emulsion layer fall in the range specified above, but the problem of sensitivity fluctuation remains unsolved. Another finding was that the use of a large amount of hardener tends to form an aggregate with gelatin, which damages the coating quality.
Generally, a silver halide color photographic light-sensitive material, hereinafter referred to as a color light-sensitive material, has a silver halide emulsion layer which has been spectrally sensitized to the desired sensitivity, wherein dye images are formed by reaction of yellow, magenta and cyan dye forming couplers in the silver halide emulsion and a color developing agent.
5-pyrazolone couplers, which have traditionally been used as magenta dye forming couplers, have major problems that yellow staining forms in the undeveloped portion in response to heat and moisture and the dye formed has undesirable absorption at around 430 nm which is undesirable from the viewpoint of color reproduction. The pyrazolobenzimidazoles described in British Patent No. 1,047,612, the indazolones described in U.S. Pat. No. 3,770,447 and the pyrazoloazoles described in U.S. Pat. No. 3,334,515, British Patent Nos. 1,252,418 and 1,334,515 and Japanese Patent O.P.I Publication Nos. 162548/1984 and 171956/1984 have very little undesirable absorption at around 430 nm and causes little Y staining due to heat or moisture.
On the other hand, there have recently been used yellow dye forming couplers which have little undesirable absorption on the long wavelength side of the spectral absorption characteristic of the dye and which offer good color reproduction, including the compound described in Japanese Patent O.P.I. Publication No. 123047/1988.
However, these magenta and yellow couplers change their color developability with changes in color developer pH, thus significantly affecting the properties, particularly gradation, of the color light-sensitive material.